package com.ppmall.util;


import java.security.AlgorithmParameters;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.Security;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import org.bouncycastle.jce.provider.BouncyCastleProvider;

public class AesUtil {
public static boolean initialized = false;  
	
	/**
	 * AES解密
	 * @param content 密文
	 * @return
	 * @throws InvalidAlgorithmParameterException 
	 * @throws NoSuchProviderException 
	 */
	public static byte[] decrypt(byte[] content, byte[] keyByte, byte[] ivByte) throws InvalidAlgorithmParameterException {
		initialize();
		try {
			Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
			Key sKeySpec = new SecretKeySpec(keyByte, "AES");
			
			cipher.init(Cipher.DECRYPT_MODE, sKeySpec, generateIV(ivByte));// 初始化 
			byte[] result = cipher.doFinal(content);
			return result;
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();  
		} catch (NoSuchPaddingException e) {
			e.printStackTrace();  
		} catch (InvalidKeyException e) {
			e.printStackTrace();
		} catch (IllegalBlockSizeException e) {
			e.printStackTrace();
		} catch (BadPaddingException e) {
			e.printStackTrace();
		} catch (NoSuchProviderException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return null;
	}  
	
	public static void initialize(){  
        if (initialized) return;  
        Security.addProvider(new BouncyCastleProvider());  
        initialized = true;  
    }
	//生成iv  
    public static AlgorithmParameters generateIV(byte[] iv) throws Exception{  
        AlgorithmParameters params = AlgorithmParameters.getInstance("AES");  
        params.init(new IvParameterSpec(iv));  
        return params;  
    }  
}
